Rotary ring-type debarker, including means for disintegrating slivers of bark



Aprll 9, 1957 p D L ET AL 2,788,034

ROTARY RING-TYPE; DEBARKER, INCLUDING MEANS FOR DISINTEGRATING SLIVERS OF BARK Filed June 24, 1955 4 Sheets-Sheet 1 7 i J I L. /2 25 4 9 23 3 E Q I3 f c O F g INVENTORS a m I? a. BRUNOELI. 4 ICE. A. JOMSSON ATTORNEYS Filed June 24, 1955 Aprll 9, 1957 P. G. BRUNDELL ETAL ROTARY RING-TYPE DEBARKER, INCLUDING MEANS FOR DISINTEGRATING SLIVERS OF BARK 1 4 Sheets-Sheet 2 INVENTORS P. 6. BRU/VDE L L ATTORNEYS KEAJONSSOM x ril 9, 1957 P. ROTARY RING-TYPE; DEBARKER, INCLUDING MEANS G. BRUNDELL ET AL 2,788,034

FOR DISINTEGRATING SLIVERS OF BARK Filed June 24, 1955 4 Sheets-Sheet 3 INVENTORS ea. BRUNDELL x. E. A. JOIVSSO/V ATTORNEYS April 9, 1957 Filed June 24, 1955 P. G. BRUNDELL ET AL ROTARY RING-TYPE; DEBARKER, INCLUDING MEANS FOR DISINTEGRATING SLIVERS OF BARK 4 Sheets-Sheet 4 INVENTORS ATTORNEYS United States Patent ROTARY RING-TYPE DEBARKER, INCLUDING llglfllgs FOR DISINTEGRATING SLIVERS 0F Per Gunnar Brundell and Karl-Erik Arnold Jonsson, Gayle, Sweden, assignors to Soderhamns Verkstader AB, Soderhamn, Sweden Application June 24, 1955, Serial No. 517,832

Claims priority, application Sweden June 28, 1954 12 Claims. (Cl. 144-208) The present invention relates broadly to the art of removing bark from logs.

More particularly, this invention is directed to improvements in a rotary debarking machine of the so-called hollow-head type where logs are fed axially in end-to-end relation through a frame mounting a rotatable ring having debarking tools thereon that are resiliently pressed against the logs.

This invention is particularly directed to improvements in rotary ring-type debarkers of the type as comprehended by our prior filed application Serial No. 418,854 filed March 26, 1954, and entitled Machine for Removing Bark Prom Logs.

The invention is particularly related to a rotary ringtype debarker in which a plurality of debarking tools are mounted for swinging movement about axes parallel to the axis of rotation of the ring and in which means are provided for continuously applying an elastic force to the tools which, when the rotating ring is either idling or under a light load, maintains the tips of the tools adjacent the axis of rotation of the ring. When a log is fed into the machine the tools will open as indicated in the abovenoted application, that is, the tool tips will move away from the axis of the ring as a result of a reaction between the revolving tools and the end face of an oncoming log. These self-opening tools will ride up the end face and onto the surface of the log and their debarking tips will become effective to remove the bark. Elastic means will urge these tips against the logs with sufficient intensity, regardless of irregularities in log contour or bark, to remove the bark without damaging the wood underlying the same. Thus, as indicated in the above-noted application, the tools remove the bark from the log without any loss of the wood layers and they operate by a shearing or scraping action substantially at right angles to the longitudinal axis of the log.

With debarking machine of this type, that is, the rotary ring, the bark removed from the log varies greatly in size. For example, when debarking frozen timber the bark, being brittle, is removed in very small pieces which can readily be disassociated from the vicinity of the barking tool by fans, scoops or the like. When bark is removed from unfrozen timber that has been stored in a pile on the ground, the pieces of bark are larger, but nevertheless they can be readily handled.

However, if a spruce-fir log is debarked in the sap period of the tree, the bark is removed from the log in long slivers. Additionally, if timber has been lying in water for a rather long period of time and is debarked, large pieces of bark are removed during the debarking operation. Thus, with such debarking, the bark as removed from the log forms balls, sometimes referred to as clues, at the log-infeed side of the debarking tools and these balls do not leave the machine until the trailing end of the log has passed the tools. Slivers of bark in these balls often have a length of 1 meter or more, and it is not unusual that the length of a sliver be the same as the length of the log.

Thus, under certain debarking conditions, bulky balls of bark are formed and in order to disintegrate these balls of bark so as to shorten the length of the slivers so that they will be better adapted for movement by conveying mechanisms and the like or be in better condition to be handled by bark presses, it is usual to arrange behind a debarking machine bark-cutting or bark-tearing mechanisms.

The present invention, therefore, has for one object to provide a rotary debarking machine of the hollowhead or rotary-ring type which incorporates a simplified bark-cutting or disintegrating mechanism.

More particularly, the present invention has for an object to provide a rotary-ring debarking machine in which the rotor is utilized as a bark cutter so that it will considerably reduce the size of the pieces of bark removed from trees, even under most difficult debarking conditions such as when debarking spruce-fir logs that have been lying in water for a number of months, for example, half a year.

Additionally, the invention has for an object to provide an arrangement in which the bark leaving the debarking machine can be directly carried away by conventional conveying mechanisms used in the art and in which the bark exit will be, in effect, a continuous stream and thus the bark leaving the machine will not be balled or agglomerated and the bark removal will be a smooth continuous operation which greatly facilitates operation of a bark press. Furthermore, since the formation of balls of bark and longer slivers which might have an injurious effect on the tools is avoided, the rotary-ring machine of the present invention provides for more uniform debarking.

It is an additional object of this invention to provide a rotary-ring debarking machine of compact construction which incorporates mechanism for disintegrating or shearing bark slivers and thus prevents the formation of balls of bark so that the axial extent of the machine can be reduced in comparison with previous machines, in that it will no longer be necessary to provide space in the machine for the exit of balls of bark.

It is believed clear, therefore, that the present invention provides a rotary ring-type debarking mechanism which not only adequately removes the bark but prevents clogging of the machine by eliminating the formation of agglomerated balls or long slivers of bark.

From a specific standpoint, it is an object of the present invention to provide a rotary-ring debarking mechanism which includes stationary shear or bark-disintegrating means in combination with debarking tools on the ring arranged to cooperate with the stationary means so that the revolving movement of the tool will establish shearing or disintegrating forces to prevent the agglomeration of bark slivers into balls and to cut or tear off long slivers to reduce their length.

From a specific standpoint, the invention provides a plurality of stationary disintegrating or cutting means for cooperation with revolving tools. The cutting means may be in the form of steel members mounted radially of the axis of rotation of the ring, or an arrangement of stationary spikes or the like.

Further and more specific advantages and objects of this invention will be apparent from the following description taken in connection with the accompanying drawings, in which:

Figure l is a longitudinal vertical sectional view as taken on the line 11 of Figure 2 diagrammatically illustrating'a rotary ring-type debarking machine incorporating one form of stationary disintegrating means,

Figure 2 is a transverse vertical sectional view as taken along the line 2-2 of Figure 1,

Figure 3 is a fragmentary transverse vertical sectional view as taken on the line 3-3 of Figure 1, and illustrates the mechanism for applying resilient or elastic force to the tools,

Figure 4 is a fragmentary cross-sectional view taken on the line 4-4 of Figure 1,

Figure 5 is an exploded perspective view illustrating a specially shaped debarking tool and the mounting therefor,

Figure 6 is a fragmentary longitudinal sectional view illustrating a modified form of the stationary disintegrating means with the section being taken along line 6-6 of Figure 6a.

Figure 6a is a fragmentary left end elevation of Figure 6 as seen from the viewing line fizz-6a of Figure 6, and further illustrates the modified form of disintegrating means,

Figure 7 is a view similar to Figure 6, but illustrating a further modification, and

Figure 8 is a fragmentary elevation of the arrangement in Figure 7 as viewed from the right.

In the embodiment illustrated in Figures 1 to 4, the log to be debarked is fed forward while restrained against rotation by roller mechanisms including rollers 2 and 3 arranged on both sides of the debarking mechanism. The debarking mechanism includes a hollow rotor or ring 4 suitably journaled on an annular ring of ball bearings for rotation relative to a stator 5. The rotor includes a sheave-forming portion 6 over which are mounted V- belts 7. The supporting structure and the drive for the V-belts is not shown. However, examples of such are embodied in the above-referred to application. On the rotor 4 are arranged a plurality of debarking tools 8. These tools have arms 19 which are crescent-shaped in elevation to provide concave edges 20, as set forth in the above-noted application, and have flanges 23 which are attached to shafts 9 that extend parallel to the axis of rotation of the rotor or ring 4. The mechanism for applying elastic force to the tools is illustrated in Figure 3, and is of the type more fully described and claimed in our prior application Serial No. 417,814 filed March 22, 1954, entitled Rotary Debarking Machine. Thus, the actuating force for the tool is effected by an elastic band means 10 trained over an adjustably mounted abutment 10 and a further abutment 11 projecting laterally of the face of a lever 11. The lever 11 includes a tubular portion splined to the shaft 9 so that when a tip of the tool arm 19 is moved away from the axis of the ring the lever 11 is turned clockwise in Figure 3 to stretch the band means 10. Thus the elastic band means applies an elastic force to each tool arm to urge the ends of the same toward the axis of rotation of the ring 4. Each of the shafts 9 passes through and is journaled by hearings in a housing 12 that is mounted on that side of the rotor structure which faces an oncoming log. Wings or fan blades 13 are also secured to the housings 12 and the entire assembly of stator, rotor, tools, force applying means, and wings or blades are surrounded by a hood 14 having a bark discharge outlet 14'. The hood 14 has an opening 16 therein on the infeed side which is circular and has a diameter somewhat larger than the diameter of the largest log for which the machine is designed to debark. The stationary disinte rating or shearing components of this modification comprise blade members arranged on the interior of a front wall 15 of the hood 14. These members, which can be termed countersteels, are denoted generally at 21 and in this modification are preferably of angle iron construction bolted to the interior of the wall 15. An edge 22 of the angle iron is disposed inwardly of the wall 15 a distance such as to be in proximity to a plane common to forwardmost portions of the concave edges of the tool arms 12. The forwardmost portions of each concave edge 20' is that portion that is closest to an incoming log. The distance between the edge 22 and said plane common to said forwardmost portions of the concave edges 20 is between 1 and 10 mms.

From a standpoint of disintegrating bark a debarking tool as illustrated in Figure 2, and more particularly in Figure 5, is highly advantageous. The crescent shaped tool arm 19 substantially contains a plane which lies at right angles to the axis of rotation of the rotor and each arm 19 has its widest end deformed laterally to provide the mounting flange 23. The flange 23 is provided with bolt-receiving apertures 24 and fits in a groove formed in a headed component 25 formed on the end of the shaft 9. Suitable bolts pass through apertures provided in the head 25 and through the apertures 24 in the flange 23 to securely mount each tool on the shaft 9. This mounting insures an arrangement in which the mounting means at no point protrudes beyond the forwardmost surface of the tool arm 19. Thus the stationary bark-disintegrating counterstcels 21 do not have to be recessed or notched to provide for clearance of any revolving components of the tool mountings and can be mounted so that they are in close juxtaposition to a path of revolution of the tools.

In Figure 5 the debarking edge of the tool is denoted at 18 and the edge-supporting portion is shown at 17. Simplified and light-weight tool construction is effected by forming the tool from a plate which is cut to shape and then bent at right angles to form the flange 23 and the edge-supporting portion 17. In debarking, therefore, with the arrangement of the abutment shear means 21, as shown in Figures 1 and 2, any slivers that are not cut adjacent the log surface by the part of the concave edge 20 that is close to the tip of the tool are for the most part torn to pieces by being sheared between the tool and the countersteels 21.

Any slivers which tend to wind themselves around the tools are cut or torn directly between the edges 22 of the steel members 21 and the concave edges 20 of the tools, regardless of the diameter of the log on which the tool is operating. With small diameter logs slivers are hurled radially outward toward the tool-carrying shafts and thus will come into the sphere of operation of the shear members 21. With large diameter logs the slivers will tend to be located close to the tip of the tools but will be subjected to the shearing action of the steel members 21 due to the revolution of the tools relative thereto.

If desirable, counterstecls or stationary members 21 can be adjustably mounted on the interior of the wall 15 for movement in directions radially of the opening 16 so that the stationary shear members can be adjusted with respect to the diameter of the logs being dcbarked.

Figures 6 and 6a illustrate a modification in which the stationary shearing components constitute spikes 26 pressed into apertures through the material of an end wall 15' of the housing 1 Figures 7 and 8 illustrate a further embodiment in which the hood or housing has been eliminated and the stationary members consist of square steel rods 28 fastened by bolts 29 and 36 to a side wall 27 of a hood 34 that surrounds the stator 5 annularly but does not include any inwardly extending end walls. Thus, in the modification of Figures 7 and 8, the hood is open at the infeed side.

Preferably the debarging tools 3 are so arranged that the arms 19 substantially contain a plane extending at right angles to the axis of rotation of the rotor or ring 4. However, if desired, the crescent-shaped arms can be bent somewhat backwards as indicated by an arm 19' in Fig. 6. Even though in this latter instance the tips of the tools do not pass quite as close to the active face of the stationary members 21, when the tools are in their outermost position the arrangement is such that any clogging is at an absolute minimum, in striking contrast to arrangements in which no stationary shear components or spikes are utilized.

Accordingly, with the incorporation of stationary shear members to cooperate with the tools carried by the rotary ring, particularly tools of generally planar shape, it is possible to provide a debarking machine which is not disturbed by clogging effect and in which the bark leaves the hood 14 smoothly and continuously and in which the distance between the end wall 15 (or 15) and the stator 5 is at an absolute minimum and is in the range of 100 to 150 mms. for machines for debarging logs having diameters varying from 8 to 16 inches.

The decrease in overall length of the machine obtained by utilizing the present invention furnishes direct as well as indirect advantages contributing to the successful debarking of timber, which not only improves the barking operation per se but simplifies the construction of the machine. The scope of the present invention, therefore, is not to be limited to the embodiments illustrated and is not to be restricted other than by the scope of the appended claims.

It is believed clear that the present invention provides a compact rotary-ring debarking mechanism which in cludes a plurality of tool members each comprising a generally planar arm of crescent shape supported for swinging movement toward and away from the axis of the rotor and having a bark-removing tip extending parallel to the axis of rotation from an outfeed planar side of the arm, and which mechanism further includes stationary shear members mounted closely adjacent an infeed side of the path of revolution of the tool-carrying arms, said shear members co-operating with the toolcarrying arms in disintegrating or shearing bark slivers and preventing the formation of balls of bark and the clogging of the debarker.

What is claimed is:

1. A rotary-ring debarker comprising a rotor through which logs to be debarked are fed, debarking tool means carried by the rotor, and stationary shear means for cooperation with the tool means for disintegrating slivers of bark removed from such logs and for preventing accumulations of bark on the tools.

2. A rotary-ring debarker as claimed in claim 1, in which the stationary shear means comprise straight-edged members mounted radially of an axis of rotation of the rotor and positioned between the tool means and an oncoming log.

3. A rotary-ring debarker as claimed in claim 1, in which the stationary shear means comprise spikes directed toward the tool means.

4. A compact rotary-ring debarking mechanism including a rotor and a plurality of tool members comprising arms of generally planar shape, each of said arms being supported for swinging movement toward and away from an axis of rotation of the rotor and having a bark-removing tip extending parallel to the axis of rotation from that planar side of the arm facing an outgoing axially feddog and stationary shear members mounted closely adjacent a path of revolution of those planar sides of the toolcarrying arms that face toward an oncoming log for cooperation with the tool-carrying arms in disintegrating or shearing bark slivers and preventing the formation of balls of bark and the clogging of the debarker.

5. In a rotary-ring debarking machine of the type in which logs to be debarked are fed axially through the ring while restrained against rotation, the combination of a plurality of generally planar tool-carrying arms distributed about the ring and mounted for pivotal movement toward and away from the axis of the ring, and stationary shearing means fixedly mounted in proximity to an infeed side of a plane common to infeed planar sides of the arms for cooperation with the arms in disintegrating long slivers of bark and preventing accumulations of bark during debarking operations.

6. In a rotary-ring debarking machine of the type in which logs to be debarked are fed axially through the ring while restrained against rotation, the combination of a. plurality of generally planar tool-carrying arms distributed about the ring and mounted for pivotal movement toward and away from the axis of the ring about axes parallel to said axis of the ring and stationary shearing means fixedly mounted in proximity to an infeed side of a plane common to infeed planar sides of the arms for cooperation with the arms in disintegrating long slivers of bark and preventing accumulations of bark during debarking operations.

7. In a rotary-ring debarking machine as claimed in claim 6, in which said arms are crescent shaped as viewed from said common plane, and in which said infeed planar sides include beveled edges.

8. In a rotary-ring debarking machine as claimed in claim 6, in which a hood surrounds said ring, a front wall of said hood being disposed in spaced relation to the infeed planar sides of said arms and having an aperture therein of a size sufiicient to accommodate the largest diameter log to be debarked, and said shearing means comprising spikes extending inwardly from an interior surface of the front wall and directed toward said ring.

9. A rotary-ring debarking machine as claimed in claim 6, in which said stationary shearing means comprise at least two straight metal shearing members disposed on opposite sides of the axis of the ring.

10. A rotary-ring debarking machine as claimed in claim 9, in which said metal shearing members extend radially of the axis of the ring.

11. In a rotary'ring debarking machine as claimed in claim 6, in which a hood surrounds said ring, a wall of said hood being disposed in spaced relation to the infeed planar sides of said arms and having an aperture therein of a size sufiicient to accommodate the largest diameter log to be debarked, and said shearing means being fixed to an interior surface of said wall.

12. In a rotary-ring debarking machine as claimed in claim 11, in which said shearing means comprise straight radially extending metal members disposed on opposite sides of the axis of the ring.

References Cited in the file of this patent FOREIGN PATENTS 31,052 Sweden June 23, 1911 140,626 Sweden June 2, 1953 1,070,548 France Feb. 24, 1954 726,404 Great Britain Mar. 16, 1955 

